package com.liang.blog.utils;

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.ExpiredJwtException;
import io.jsonwebtoken.JwtParser;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.io.Decoders;
import io.jsonwebtoken.security.Keys;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.Assert;

import java.security.Key;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
@Slf4j
public class JwtUtils {
    private static long expiration = 30 * 60 * 1000;//30分钟

    private static String secretString = "JgrKZsRWra+i3EWXUGbiTotHYl6gLwwwOwLf8xPlanc=";
    private static Key key = Keys.hmacShaKeyFor(Decoders.BASE64.decode(secretString));//字符串转成byte

    /**
     * 生成令牌
     * @param claims
     * @return
     */
    public static String genJwt(Map<String, Object> claims) {

        return Jwts.builder()
                .setClaims(claims)
                .setExpiration(new Date(System.currentTimeMillis() + expiration))//过期时间
                .signWith(key)
                .compact();
    }

    /**
     * 校验令牌
     * @param token
     * @return
     */
    public static Claims verify(String token) {
        JwtParser build = Jwts.parserBuilder().setSigningKey(key).build();
        Claims claims = null;
        try {
            claims = build.parseClaimsJws(token).getBody();
        } catch (ExpiredJwtException e) {
            log.error("token过期，校验失败，token:" + token);
        } catch (Exception e) {
            log.error("token校验失败，token:" + token);
        }
//        } catch (Exception e) {  签名异常
//            log.error("token校验失败，token:" + toke n);
//        }
        return claims;
    }

    public static Integer getUserIdFromToken(String token) {
        Claims claims = verify(token);
//        if(claims == null) {
//            return null;
//        }
        Assert.notNull(claims, "token不合法");
        Integer userId = (Integer) claims.get("id");
        return userId;
    }
}
